The plans are freely available, just can't find them back on the forum...look for the attachement in this post. The engine has been constructed from 1mm 304 stainless steel. Never realy weighed the engine but I think it's around 3 pounds. You can round off the dimensions to 1 digit behind the period e.g., 39.356 = 39.4

Make sure you follow the plans as close as possible.

If you're having trouble with some of the layouts (like with the choke cone and the hole alignment) let me know.

If I knew how to fuel this engine efficiently with liquid fuel I'd be flying it myself. It's very hard to do. I have some ideas and a somewhat promising prototype but all testing has been put on hold indefinitely.

I was messing around with a liquid fueled M25 a couple of years back. I never realy properly tested it but I did build a single intake version of the engine so here are the plans if anyone's interested (all dimensions internal)